Payment Method Additional Fee

sorry if the question is stupid but i've search all the forum without find any awnser

nop commerce 1.4 seem to support the payment additional fee but how can i set it??

and another important thing... it is possible to map shipping method with payment method?

very thanks for the help

1. Open your payment gateway source code file (implements IPaymentMethod), find GetAdditionalHandlingFee method and return the required fee. Then recompile this assembly.
2. It's not possible to map shipping method with payment method